With the social progress and technical development, the volume and thickness of the terminal electronic device are reduced, and correspondingly, the volume of the micro-loudspeaker cooperated therewith becomes smaller and smaller. However, the requirement on the performance of products, especially on the heavy bass effect of sound, is increasingly higher. As for speaker modules with a smaller volume, it is difficult to achieve ideal bass effect due to the limitation on the volume.
The speaker module usually comprises a speaker unit and a plurality of housings provided around the speaker unit. The speaker unit usually comprises a vibration system and a magnetic circuit system. The vibration system comprises a vibrating diaphragm and a voice coil. The magnetic circuit system forms a magnetic gap for accommodating the voice coil. The vibrating diaphragm vibrates under the driving of the voice coil, so as to produce sound which is radiated to outside to be heard. A front acoustic cavity and a rear acoustic cavity separated from each other are formed between the vibrating diaphragm and the housings, the front acoustic cavity is in communication with the sound hole of the speaker module, and the rear acoustic cavity is typically an enclosed structure. The larger the volume of the rear acoustic cavity, the better the bass effect is. However, due to the limited space of the speaker module, it is hard to achieve the desired bass effect.
Thus, it is required to provide a speaker module to solve the above problems.